Electroacoustic transducers, such as loudspeakers, are devices that convert electrical energy into acoustic oscillations. Electroacoustic transducers are utilized in many consumer products, such as household stereo systems, home theater systems, audio systems for automobiles, portable music devices, headphones, recording studio equipment, acoustic sensory equipment, and others. Demand for high quality sound production and/or recording from these and other products has generated great interest in the development of electroacoustic transducers that can convert electronic signals into sound waves with greater accuracy and higher definition.
One problem with known electroacoustic transducers is their reliance on moving components (e.g., voice coils and diaphragms) to produce acoustic oscillations in a two-step energy conversion process. In the first step, electric energy of a sound signal is converted into mechanical vibrations of a membrane attached to the electro acoustic transducer. In the second step, the mechanical vibrations of the membrane create acoustic oscillations in a surrounding gas medium (e.g., air). The membrane has a certain mass, a finite, limited rigidity, and given boundaries, which affect the quality of sound reproduced in the surrounding space during the second step. Thus, the quality of sound reproduction is physically limited by these aspects of the membrane. Some manufacturers have sought to overcome these challenges by producing different types of electroacoustic transducers that operate without the use of moving parts. For example, electroacoustic devices have been developed that create sound waves using areal electric discharge.
U.S. Pat. No. 9,445,202 to Chyzhov (hereby incorporated by reference) describes an electroacoustic transducer that includes an anode and a cathode, each including discharge elements. One or both of the electrodes (i.e., the anode and cathode) are separated into sections by dielectric barriers. Corresponding discharge elements of the cathode and anode are positioned opposite each other, their terminal ends extending equidistantly into a space between the cathode and the anode (i.e., an inter-electrode space). An active surface area (S) of the discharge elements of the anode and cathode satisfy the expression Sanode/Scathode>1. The discharge elements are configured as discrete or solid bodies with a linear cross-sectional length not greater than 3 mm. The electrode sections are separated from one another by dielectric barriers connected to a voltage source through a current-limiting element (i.e., a resistor).
While the electroacoustic transducer of the '202 patent may be operable to create sound waves, further improvements may be realized. For example, one problem experienced in the operation of electroacoustic transducers utilizing electrical discharge to create acoustic waves is that the stability of the discharge process may be reduced when the power output of the generated acoustic signal is increased during operation of the device. Accordingly, there is a need for improved electroacoustic transducers having improved efficiency and increased stability of the discharge process.